Signal-bell.



PATENTED NOV.-5, 1907. G. F. DREW.

SIGNAL BELL.

APPLIOATION FILED 001.13.1908.

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GEORGE F. DREW, OF BRUNSWICK, MAINE.

SIGNAL-BELL.

Specification of Letters Patent.

Patented Nov. 5, 19.07.

Application filed October 13, 1906. Serial No. 338.767.

To all whom it may concern:

Be it known that I, GEORGE F. DREW, a citizen of the United States of America, and a resident of Brunswick, in the county of Cumberland and State of Maine, have invented certain new and useful Improvements in Signal-Bells, of which the following is a specification.

My present invention relates to a new and novel improvement in bells or gongs, and more particularly to the electric or electro-magnetic type of bells, such for example as are employed for signaling in connection with telephones or other apparatus or devices located in electric circuits in which call-bells arranged in pairs are included.

In bells of the class referred to and as usually constructed the hammer or striker member is located and arranged to vibrate rapidly between and strike the adjacent peripheral surfaces of a pair of suitably mount ed laterally separated stationary metallic bells or resonant members, the action of the hammer being responsive to a suitably controlled electro-magnet or other electrical apparatus in which the hammer movements are due to the employment of an electric current.

The object I have in view is to produce a bell of the character referred to so that a single gong or analogous member may be employed with equal or greater efficiency than a bell having a pair of gongs as generally devised and used.

My improved single bell requires only about one-half the room or space occupied by a double-gong bell, assuming each of the latter and the said improved gong to be substantially alike in size or diameter. Another advantage possessed by my improved bell is that the cost of manufacture is materially less than the former or well-known type ofdouble-gong bells, while at the same time having equal or greater efficiency, as before stated.

I am of course well aware that plain, single electric bells have been long employed and I therefore dis claim such former devices. My invention, however, differs materially from the latter in that the gong or resonant member proper is so constructed that when in use opposite points of the hammers surface strike adjacent parts of one and the same gong, the sound emitted being practically continuous and non-distinguishable from that produced when a single-hammer double-gong bell is used. In a bell having a single hammer and a single gong as usually made the signal produced consists of intermittent ringing sounds, the contact action or blows of the vibrating hammer against the gong obviously being only one-half that produced by a hammer vibrating at the same rate of speed upon a pair of gongs.

In my improved bell the invention consists, essenv tially, in providing the gong or resonant member itself with a plurality of suitably located oppositely disposed integral flanges or webs between which latter the hammer or striker member is mounted to vibrate so that when in use it alternately strikes said flanges, all as hereinafter set forth and claimed.

In the accompanying sheet of drawings, Figure 1 represents a plan or top View of a gong or resonant member embodying my improvement. Fig. 2 is a corresponding central sectional view, taken on line 2 2 of Fig. 1. Figs. 3 and 5 i are plan views representing modified forms of the invention, and Figs. 4 and 6 are sectional views, taken on lines 4 4 and 6 6, respectively, of said Figs. 3 and 5.

I would state here in explanation that while devices of the type or class herein referred to are generally termed electric-bells, signal -bells or call-bells, my invention relates solely to improvements in the cup or saucer-shaped member which gives out a ringing sound when struck with a hammer. In order to designate said member of the bell I have in this application termed it the gong or gong member.

My improved gong member a, illustrated herewith, may be made of suitable metal or composition of metals possessing the-proper or desired degree of resonance substantially as common, and formed from sheet metal or cast metal stock as may be deemed most practicable and desirable. In fact the general form and size of the gongs may if desired be made substantially the same as those heretofore used and be readily substituted therefor. In the drawings the gong a is represented as being round and having a semi-oval of inverted saucerform cross-sectionally, its general shape being substantially like the well-known signal or call-bells used in connection with telephone apparatus, &c. The gong shown in .Figs. 1 and 2 may be cut from sheet-metal stock and pressed into shape by means of suitable dies and tools. The invention resides in providing the gong with a pair of diverging sides or flanges, b b, the

ment represented in said figures a comparatively deep well-rounded D -shaped depression 0 is formed in the Wall of the gong at its periphery, said flanges being integral with the stock and forming a tie or bridge b at the bottom of thesaid opening 0. I prefer to provide the center of the gong on top with an elongated hole f, the longitudinal axis of the hole being in substantial alinement with a line extending longitudinally through the center of the opening 0.

The usual hammer or striker h. is or may be secured to the free end of a suitably mounted and actuated rod or stem 8 and adapted to be'rapidly vibrated in a lateral direction through the medium of an electrically energized magnet or other analogous controlling means in any well-known manner. The normally stationary position of the hammer is about midway or central of the said space a, lying between the adjacent surfaces of the divergent flanges b, as clearly indicated in the drawings. By means of a suitable bolt adapted to pass through the elongated hole f and a clamping nut therefor the position of the gong may be readily adjusted or positioned with respect to the relatively stationary hammer h. As'combined adjusting and securing means for this purpose are well-known and frequently employed the same constitutes no part of my present invention, therefore such bolt and nut or securing means are omitted from the drawings. The extent of the lateral vibratory movements of the hammer may be changed at will, or in other words the stroke of the hammer may be lengthened or shortened by simply changing the position of the gong so 'asto correspondingly increase or decrease the distance between the bottom b of the recess 0 and the center of the hammer.

In the modified formsof the gongsashown in Figs.

3 to 6, inclusive, the arrangement of the divergent flanges b and the manner of locating the hammer between them are substantially the same as represented in Figs. 1 and 2. It is obvious too that the hammer h will work equally as well in case its shank s is located in a vertical plane with respect to the base of the gong in lieu of being parallel with it, the latter arrangement being represented in thedrawings.

I claim as my invention and desire to secure by United States Letters Patent:-

1. As a new article of manufacture, an integral or onepiece bell having one side or portion thereof formed so as to produce therein a continuously open recess having walled sides between which a striker may freely vibrate, for the purpose hereinbefore set forth.

2. As an improved article of manufacture a gong or analogous resonant member having a side thereof depressed so as to form therein a continuously open vertical recess 0 having walled sides between which a striker may freely vibrate, said walled sides extending inwardly from the outer edge of the gong in a convergent manner.

Signed at Brunswick, Me., this 11th day of October, 1906.

GEORGE F. DREW.

Witnesses Crnss. DICKINSON, Jacob H. HENLEY. 

